code: def num_processes(self):
      return 1
  
file_path: SynapseML/deep-learning/src/test/python/synapsemltest/dl/conftest.py
imports: import os
  import shutil
  import subprocess
  import urllib
  from os.path import join
  import numpy
  import pandas
  import pytest
  import torchvision.transforms
  from pyspark.ml.feature import StringIndexer
label_desc: Use image node_id 2 for calling the CallbackBackend obj's underlying member method code with example usage: obj.num_processes() and returns: int